1. Field of the Invention
This invention relates to certain 2,6-dioxocyclohexylidene derivatives. In one aspect, the invention relates to novel compositions which exhibit herbicidal activity against a variety of broadleaf and grassy weeds. In another aspect, the invention relates to a method of controlling undesirable plant growth, by applying a herbicidally effective amount of said compositions to the plants. In a further aspect of the invention, certain of the compositions show cotton defoliant activity.
2. Description of the Prior Art
The present invention relating to the 2,6-dioxocyclohexylidene derivatives and their herbicidal activity originated during an investigation which is described in U.S. Ser. No. 288,335 filed July 30, 1981. This prior investigation relates to certain herbicidal 2-(2-pyridinyl)-1,3-cyclohexanediones typified by the following: ##STR1##
The compounds of this invention differ from the above described pyridinyl diones in having non-aromatic rings attached to the 1,3-cyclohexanedione 2-position by a double bond.
Furthermore, prior to the present invention, certain structures included within the scope of this invention had been investigated for their antihypertensive properties. For example, T. Tsujikawa et al., in Heterocycles 6 (3) 261-266 (1977) and Chem. Pharm. Bull. 25 2775 (1977), reported certain 2-(2-pyrrolidinylidene)-; 2-(2-piperidinylidene)-; and 2-(hexahydro-2H-azepin-2-ylidene)-1,3-cyclohexanediones and their derivatives.
In addition, T. Hatada et al in Yakugaku Zasshi. 95 623 (1975) reported certain 2-(2-imidazolidinylidene)-1,3-cyclohexanedione structures, albeit herbicidal use was not disclosed.
The closest prior art compound structurally with known herbicidal activity to the compounds of this invention is the following disclosed in Japanese Patent 11,097 patented Apr. 10, 1973 (Chem. Abst. 79 32037g (1973)): ##STR2## which differs from all of the subject compounds by the presence of a sulfur atom in the heterocyclic (thiazolidine) ring.